The Arduino Pro was designed and manufactured by SparkFun Electronics. It is a more embedded version of the Arduino, with an original Arduino I/O footprint, but a slightly smaller card. The Arduino Pro has no I/O connectors, or USB to Serial converter in order to keep the complexity low.

The Arduino Pro Mini was designed and is manufactured by SparkFun Electronics. It is an even more embedded board than the Arduino Pro, with reduced I/O footprint. The Arduino Pro Mini has no I/O connectors, or USB to Serial converter. It is available in 16MHz running on 5V, or an 8MHz 3.3V version.

Intel and Arduino. Arduino compatible using a Quark 400MHz system on a chip. It leverages the Arduino IDE to generate Intel code to run on the Pentium class Quark processor. It is compatible with 5V or 3.3V shields.

The original LilyPad was designed by Leah Buechley and SparkFun Electronics as a wearable (and apparently washable) device for electrifying clothing. It runs either an ATmega168V or ATmega328V for low voltage use. There is no voltage regulator or protective diode, so care must be taken with the power supply.

The LilyPad Arduino Simple Snap is a Lilypad Simple, with snaps for I/O connections, so the entire board can be removed from the project. The board has a lithium battery and a charging circuit. It was designed by Leah Buechley and SparkFun Electronics.